TDI Conversion ( Sharan / AFN ) - My Build Diary

[ewenmaclean]

yep - of course the important line not shown there is the one from a boost pipe source to the MAP sensor on the ECU! I'm guessing you already have that sorted!

You can ignore EGR for the moment by the way, but you'll get some error codes - easy to disable that if you want too with blanking plates and some messing about with VCDS.

Ewen

[16vmini]

hmmm went to start it this morning and it just turned over without firing ..i had to bleed/pump diesel through before it would start ...

not sure why it would have got air back into it ?

Matt

[ewenmaclean]

Hello,

common culprit is the thermostatic t-piece and o-ring seal on the fuel filter, but could be lots of things. I'd fit a non-return valve in any case just before the IP - air ingress can be hard to track down. Copper seals on the IP, main seal on the IP itself, bleed-off pipes and badly fitting clips on pipes can all contribute so check all them, but I'd fit a valve. I've also got a lift-pump on mine which is quite useful for repriming.

Ewen

[16vmini]

Hello,

common culprit is the thermostatic t-piece and o-ring seal on the fuel filter, but could be lots of things. I'd fit a non-return valve in any case just before the IP - air ingress can be hard to track down. Copper seals on the IP, main seal on the IP itself, bleed-off pipes and badly fitting clips on pipes can all contribute so check all them, but I'd fit a valve. I've also got a lift-pump on mine which is quite useful for repriming.

Ewen

ok will have a check over ...as my old engine did not have a problem .. i guess i connected it up correctly ! LOL

did some jobs on it last night now its home ...

bodged an old air filter on to flow meter ...




been tiding up wiring ... (trust me it was worse than this ! )



and this is how i am driving at the moment :

[ewenmaclean]

ok sorry - ignore the thermostatic t-piece suggestion, I see you haven't got one! Also it looks like you have a primer with non-return valve on the fuel inlet, so non-return valve is no help either. If I'm right about that then it might be the bleed off pipes and final blanking cap causing the fuel to return to the tank - I did have that once on mine.

Good luck sorting the rest out - hope it runs properly soon.

Ewen

[16vmini]

... bleed off pipes and final blanking cap causing the fuel to return to the tank -

the what and what ? .. off to google

Matt

[ewenmaclean]

sorry - the pipes that go between the injectors. Cylinder 1 has a blanked off one, and Cylinder 4 injector as a longer part going back to the IP return line.

http://www.brickwerks.co.uk/shop?page=s ... gory_id=96" onclick="window.open(this.href);return false;

and

http://www.brickwerks.co.uk/index.php?p ... t&Itemid=3" onclick="window.open(this.href);return false;

although I can't promise that's the culprit!

[16vmini]

ok i plumbed in the boost control last night .. no difference yet...

allthough i have found if i rev the engine hard after starting it drives ok ish .. ie if i dont rev it .. its like its in limp home mode ?

but ... one running good ... i am still only getting 1psi of boost !!! which is not right ....

now would my exhuast be causing the problem ? as i just bodged my 1.6D one on for now , and its not very big in diameter compared to the std AFN one ??? restriction ?

regards

Matt

[16vmini]

he's my bodged exhaust ... would this really restrict it to 1psi .. i know its not going to help but should i try replacing with bigger system first or try something else ?

[ewenmaclean]

Hello,

It won't be the exhaust I'm pretty sure. It sounds like you're not getting any vacuum to the vane actuator to me. In Vcds you can run an "output test", but I'd check you have a vacuum source at the n75, and that you're sure it's all wired up and plumbed together. Check for vacuum to the actuator and check the actuator pin actually moves - these get gunged up over time.

Ewen

[16vmini]

Hello,

It won't be the exhaust I'm pretty sure. It sounds like you're not getting any vacuum to the vane actuator to me. In Vcds you can run an "output test", but I'd check you have a vacuum source at the n75, and that you're sure it's all wired up and plumbed together. Check for vacuum to the actuator and check the actuator pin actually moves - these get gunged up over time.

Ewen

how do i check what turbo i have ? ie , is it a waste gate operated one or a Vane operated one ? or do they look same etc ?

also then by default is the vanes/wastegate OPEN by default so no boost. . and a vacum is needed to make boost ! ? through n75

Matt

[ewenmaclean]

Since you said Afn I am assuming vnt. Does it have a wastegate? You made the exhaust so you would have seen - if you just see one port with a turbine then it's vnt - two ports with a wastegate then it's not.

On a vnt the more vacuum the more the Vanes are directed to the outside of the turbine wheel causing a more concentrated jet and more boost. With no vacuum you''ll get very little boost.

Limp mode does give you boost though, just very restricted fuelling. The other mode is when you get no revs at all until you rev hard then it's fine - this is usually if your pedal switches aren't connected or earthed.

[ewenmaclean]

Just checked through your pics - that's a vnt...

[16vmini]

Just checked through your pics - that's a vnt...

cool , was just going to say i have one port ...

ok will have a double check of things .. sorry for being stupid

at the moment all my pedal switches are just taped closed in the loom

Matt

[ewenmaclean]

Do you have access to vcds? Useful for debugging and easy to set up.